Diffusion Breast MRI: Current Standard and Emerging Techniques.

The role of diffusion weighted imaging (DWI) as a biomarker has been the subject of active investigation in the field of breast radiology. By quantifying the random motion of water within a voxel of tissue, DWI provides indirect metrics that reveal cellularity and architectural features. Studies show that data obtained from DWI may provide information related to the characterization, prognosis, and treatment response of breast cancer. The incorporation of DWI in breast imaging demonstrates its potential to serve as a non-invasive tool to help guide diagnosis and treatment. In this review, current technical literature of diffusion-weighted breast imaging will be discussed, in addition to clinical applications, advanced techniques, and emerging use in the field of radiomics.

Noncontrast MRI with advanced diffusion weighted imaging for breast cancer detection in a lactating woman.

Magnetic resonance imaging (MRI) is used for preoperative evaluation, high-risk screening, and other select indications for breast cancer. However, the interpretation of breast MR images in pregnant and lactating women is complicated by physiologic changes of the breast that may result in marked background enhancement. Breast MRI with contrast administration is contraindicated in pregnancy. Restriction spectrum imaging (RSI) is an advanced diffusion-weighted (DW)-MRI method that theoretically reflects signal from cells with high nuclear-to-cytoplasm ratio without gadolinium-based contrast. This report describes a case in which RSI notably increased tumor conspicuity in a lactating woman, compared to contrast-enhanced (CE)-MRI and conventional DW-MRI.

Regional therapies for in-transit disease.

In-transit melanoma is an uncommon pattern of recurrence, but presents unique management challenges and opportunities for treatment. The clinical presentation usually involves from 1 to more than 100 small subcutaneous or cutaneous nodules, ranging from submillimeter to multiple centimeters in diameter. Regional chemotherapy techniques are a mainstay of treatment of patients without systemic disease spread. Future applications of regional therapy are likely to involve combination therapy with cytotoxic agents and novel immune modulators. Regional therapy provides distinct opportunities for the treatment of unresectable disease, and offers a unique platform for investigation of novel therapeutics in early-stage clinical trials.